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Synthesis and Crystal Structure of 2-Hydroxybenzoic Acid [1-(3,5-Dibromo-2-hydroxyphenyl)methylidene]hydrazide Methanol

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Chinese Journal of Structural Chemistry 2007年第5期26卷 547-550页

作者： WANG Nong LI Jing-Ping pu yan-Ling School of Chemical and Biological Engineering Lanzhou Jiaotong University Lanzhou 730070 China

A new Schiff base compound, 2-hydroxybenzoic acid [1-（3,5-dibromo-2-hydroxyphenyl） methylidene]hydrazide methanol （C14H10Br2N2O3·CH3OH）, has been synthesized by the condensation of equimolar 3,5-dibromosalicylaldehyde and 2-hydroxybenzoic acid hydrazide in a methanol solution. The compound was characterized by elemental analysis, IR spectra, and singlecrystal X-ray diffraction. The compound consists of a Schiff base moiety 2-hydroxybenzoic acid [1-（3,5-dibromo-2-hydroxyphenyl）methylidene]hydrazide and a lattice methanol molecule. The crystal belongs to the monoclinic system, space group P21/n with a = 7.183（1）, b = 15.673（2）, c = 15.001（2） A, β = 98.345（2）°, Z = 4, V = 1670.9（4） A^3, Dc = 1.773 g/cm^3, Mr = 446.10, λ（MoKα） = 0.71073 , μ = 4.872 mm^-1, F（000） = 880, R = 0.0458 and wR = 0.0963. A total of 3445 unique reflections were collected, of which 2236 with I 〉 2σ（Ⅰ） were observed. As expected, the molecule adopts a trans configuration about the C=N double bond. The two benzene rings are nearly coplanar （mean deviation from the combined plane is 0.061（4） ）, with the dihedral angle of 7.9（3）°. The preliminary biological tests show that the compound has moderate antibacterial activities.

关键词： Schiff base acylhydrazone crystal structure antibacterial activity

The Method of Combined Inspection

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 235-242页

作者： Wei-qing Zhang Xiao-long pu yan Li School of Finance and Statistics East China Normal University Shanghai 200241 China

For costly and/or destructive inspections for a complex population, the sum of observations, the test statistic in common use, is shown to be inefficient in risk control. For the complex population consisting of Bernoulli distributions, the method of combined inspection is proposed in this paper, Evaluation based on examples and simulation results is conducted according to the method of limited classification. It is concluded that the new method is efficient and applicable.

关键词： Method of combined inspection sampling inspection complex population overall classification limited classification

Spectral matching algorithm based on nonsubsampled contourlet transform and scale-invariant feature transform

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Journal of Systems Engineering and Electronics 2012年第3期23卷 453-459页

作者： Dong Liang pu yan Ming Zhu Yizheng Fan Kui Wang Key Lab of Intelligent Computing ＆ Signal Processing Ministry of Education Anhui University Hefei 230039 E R. China School of Electronics and Information Engineering Anhui University Hefei 230039 P. R. China School of Mathematics and Computation Sciences Anhui University Hefei 230039 P. R. China

A new spectral matching algorithm is proposed by us- ing nonsubsampled contourlet transform and scale-invariant fea- ture transform. The nonsubsampled contourlet transform is used to decompose an image into a low frequency image and several high frequency images, and the scale-invariant feature transform is employed to extract feature points from the low frequency im- age. A proximity matrix is constructed for the feature points of two related images. By singular value decomposition of the proximity matrix, a matching matrix （or matching result） reflecting the match- ing degree among feature points is obtained. Experimental results indicate that the proposed algorithm can reduce time complexity and possess a higher accuracy.

关键词： point pattern matching nonsubsampled contourlet transform scale-invariant feature transform spectral algorithm.

Effect of Co on the martensitic transformation,crystal structure and magnetization of Ni_(52.5) Mn_(23.5) Ga_(24) based ferromagnetic shape memory alloys

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Chinese Science Bulletin 2011年第8期56卷 796-802页

作者： yan ShaoMeng pu Jian CHI Bo LI Jian School of Materials Science and Engineering State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology Wuhan 430074 China

Five(Ni52.5Mn23.5Ga24)100-xCox(x = 0,2,4,6,8) alloys were prepared by arc melting,and the effects of Co addition on the martensitic phase transformation,crystal structure and magnetization were *** phase transformation temperatures Ms,Mf,As and Af are proportional to the content of Co in the(Ni52.5Mn23.5Ga24)100-xCox alloys,which appears to be due to the variation in the valance electron *** Curie temperature is sensitive to the composition of the *** the amount of Co changes,both the Co-Mn exchange interaction and the distance between Mn atoms ***,in turn,affect the Curie temperature and magnetization behavior of the *** martensite phases in all the alloys are domained in three different orientations,the domain boundary was determined to belong to the family of {112} lattice planes.

关键词：铁磁形状记忆合金马氏体相变晶体结构磁化强度 Co 真空电弧熔炼相变温度电子浓度

An improved procedure for the synthesis of 4-methylimidazol-2-one

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Chinese Chemical Letters 2007年第7期18卷 777-778页

作者： Hong Shu yan Qing Wang pu Qin Cai Chun Guo School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 China

A novel one-pot synthetic method of 4-methylimidazol-2-one is described. The target compound is conveniently synthesized from sodium diformylamide, a modified Gabriel reagent prepared, through condensation, hydrolyzat... 详细信息

关键词： 4-Methylimidazol-2-one Synthesis Sodium diformylamide

Performance Analysis of TCP-Reno and TCP-Sack in the Case of a Single Source

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Wuhan University Journal of Natural Sciences 2000年第1期5卷 70-74页

作者： Wang, Xin-miao yan, pu-liu Huang, Tian-xi Wuhan Univ Wuhan China

This work explores the behavior of both TCP-Reno and TCP-Sack under a simple scenario, where a single TCP source transmits the packets continuously over a single bottleneck node characterized by its queue size, bandwidth and propagation delay. The analysis allows to derive the performance of TCP, the utilization tends to 75% of the bottleneck throughput when the bandwidth×propagation delay pipe becomes very large, while it tends to 100% when the queuing delays are predominant because the queue is never empty. In the transient analysis we show how the initial phase of the session can degrade the performances. These results are proved through simulation.

关键词： Bandwidth Congestion control (communication) Packet networks Telecommunication traffic

A Nimble Cloning-compatible vector system for high-throughput gene functional analysis in plants

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Plant Communications 2023年第2期4卷 65-76页

作者： pu yan Decai Tuo Wentao Shen Haida Deng Peng Zhou Xinzheng Gao Key Laboratory of Biology and Genetic Resources of Tropical Crops Sanya Research InstituteInstitute of Tropical Biosciences and BiotechnologyChinese Academy of Tropical Agricultural Science&Key Laboratory for Biology and Genetic Resources of Tropical Crops of Hainan ProvinceHainan Institute of Tropical Agricultural ResourcesHaikou 571101China Department of Biology Hainan Medical UniversityHaikouChina

Plant expression vectors are essential tools for gene functional analysis and molecular plant *** gene of interest is transferred to the vector by molecular cloning *** Cloning is a newly developed molecular cloning method with the advantages of simplicity,efficiency,and *** this study,we developed a"pNC"vector system that contains 55 Nimble Cloning-compatible vectors for functional analysis of genes in *** vectors contain the NC frame flanked by unique adapters for one-step and standardized Nimble *** demonstrate that the pNC vectors are convenient and effective for the functional analysis of plant genes,including the study of gene ectopic expression,protein subcellular localization,protein-protein interaction,gene silencing(RNAi),virus-induced gene silencing,promoter activity,and CRISPR-Cas9-mediated genome ***"pNC"vector system represents a high-throughput toolkit that can facilitate the large-scale analysis of plant functional genomics.

关键词： nimble cloning plant expression vector gene function ectopic expression genome editing

Research on inversion method for complex source-term distributions based on deep neural networks

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Nuclear Science and Techniques 2023年第12期34卷 159-176页

作者： Yi‑Sheng Hao Zhen Wu yan‑Heng pu Rui Qiu Hui Zhang Jun‑Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging of Ministry of Education Beijing 100084China Nuctech Company Limited Beijing 100084China

This study proposes a source distribution inversion convolutional neural network (SDICNN), which is deep neural network model for the inversion of complex source distributions, to solve inversion problems involving fixed-source distributions. A function is developed to obtain the distribution information of complex source terms from radiation parameters at individual sampling points in space. The SDICNN comprises two components:a fully connected network and a convolutional neural network. The fully connected network mainly extracts the parameter measurement information from the sampling points,whereas the convolutional neural network mainly completes the fine inversion of the source-term distribution. Finally, the SDICNN obtains a high-resolution source-term distribution image. In this study, the proposed source-term inversion method is evaluated based on typical geometric scenarios. The results show that, unlike the conventional fully connected neural network, the SDICNN model can extract the two-dimensional distribution features of the source terms, and its inversion results are better. In addition, the effects of the shielding mechanism and number of sampling points on the inversion process are examined. In summary, the result of this study can facilitate the accurate assessment of dose distributions in nuclear facilities.

关键词： Source term inversion Monte Carlo Artificial intelligence Neural network

A 3-D Differential Method for Solving Rolling Force of PC Hot Strip Mill

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Journal of Iron and Steel Research International 2010年第9期17卷 36-39页

作者： WANG Xue-song PENG yan XU Li-pu LIU Hong-min State Key Laboratory of Metastable Materials Science and Technology Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao 066004 Hebei China

The character of the deformation zone on pair cross rolls is different from that of the regular 4-high mill. Considering comprehensive influences of normal stress and shear stress in rolling direction, width direction and thickness direction, the rolling force calculation model of the PC （pair crossed） hot strip mill is built. Taking the entry stress and the exit stress of strip as the boundary conditions, the longitudinal and transverse distribution of rolling force is worked out by the differential method. Then the total rolling force is calculated, and calculated results are verified by experimental data.

关键词： PC rolling mill rolling force differential method model building